So there is mention of making a MND save in the description for minor magic, but saving throws are not defined anywhere.

Actually, there are rules for saving throws. One sentence ("Saving throws are handled as skill checks.") in the section on Skill Checks. Hmm, I probably need to make that stand out a bit more since you missed it and you are going through the rules with a fine tooth comb.

The other is the description for acid arrow mentions a ranged touch attack, but touch attacks are also not defined.